The present invention relates to a switch with a selective release, and more particularly to a switch having a stroke armature which is activated by current corresponding to the switch release current.
In prior art switches such as that disclosed in German Patent Publication (Offenlegungsschrift) No. 2,854,568 Greefe there is a stroke armature with a selective release with spring action mounted in a moveable fashion in the interior of an electromagnetic coil. The release is further equipped with a lever arrangement which is rotatably mounted on a shaft and consists of a two-armed, L-shaped lever and a further single-armed lever which is swivel-mounted on the L-shaped lever. The two levers always form one stop for the stroke armature. In the rest position the single-armed lever is located outside the reach of the stroke armature. At the first release current pulse the stroke armature is drawn into the electromagnet coil and upon conclusion of the current pulse it swings back. The armature thereby butts against the first stop (L-shaped lever) of the lever arrangement and moves it into a position in which the second stop (single-armed lever) moves within range of the stroke armature. If a second release current pulse arises before the lever arrangement has swung back into its rest position, the stroke armature is drawn again into the coil and impacts against the single-armed lever. Due to the action of the stroke armature this lever trips and thereby actuates a latch of a current limiting switch using an additional lever. It will be appreciated that it would be highly desirable to produce a switch having a similar function but of simpler design, and fewer operating elements.
It is therefore an object of the invention to provide a switch with a selective release having the lowest possible number of moveable parts.
Another object is to provide a switch with a selective release which exhibits improved reliability.